I run Datamine 2 now for a couple of months , but everytime there is a LUA restart I get in blue the message: dataMine 2 graphing [307] : Running Lua Startup" which takes a very very long time to clear, I am talking about 20-30 minutes ( minimum) .

Why is this , is this bad? In the beginning it didn't take so long. Is my USB stick getting full? too much data?

not sure, it never takes that long with me and i have it up and running for several years. i never liked the usb solution though. i have the files on my NAS and connect Vera to the nas rather than usb stick. not sure if thats your problem